package oop9;

import oop6.pet2.Dog;

import java.io.ObjectInputStream;

/**
 * @author oldliu
 * @since 1.0
 */
public class TestNull {
    public static void main(String[] args) {
        Object o=null;
        System.out.println(o instanceof Object);
        Dog d=null;//
        System.out.println(d instanceof Dog);
        Dog d3=(Dog)o;

    }
}
